Unintended pregnancy remains a stubborn problem in the United States, particularly among younger women. Better access to long-acting reversible contraception (LARC) may help this population avoid unintended pregnancy and the dilemmas of considering abortion. The questions are whether LARC can be sufficiently desirable to use, and provide better protection from unintended pregnancy relative to the alternatives. Currently, many barriers prevent uptake of LARC, and thus a true measure of its potential is unknown. If LARC is found to be superior to other methods, more effort can be made to rejuvenate existing health programs and ensure that LARC is a guaranteed option for all those who want it. In the proposed study, women aged 18-29 seeking oral or injectable contraception will be offered an opportunity to try LARC instead;the FDA-approved options include two types of intrauterine products and one type of subdermal contraceptive implant. Over a 12 month period, the experiences of LARC users will be compared to the experiences of those opting for their initial short-acting method. It is expected that 38% of participants using short-acting methods will stop using them during the first year and be at risk of unintended pregnancy;in contrast, less than 20% of LARC users will want to have their contraceptive removed. Continuation rates will be measured and pregnancies will be tallied in the two groups to document any differences that emerge. To assemble the proper evidence for fair comparisons, innovative strategies are needed. First, a hybrid intervention trial will be used to recruit two types of participants: those who have strong preferences for a particular method and those who would be willing to use a randomly assigned option. The randomized component and analysis will be used to isolate the contribution LARC can have in preventing unintended pregnancy. The cohort formed by choice of method will be used to document natural use patterns and provide comparative data. Participant attitudes toward LARC will identify barriers to more widespread uptake;a qualitative sub-study consisting of in-depth participant interviews will collect nuanced data on reasons for uptake and discontinuation of short and long-acting methods. The evidence gathered from this study will help determine whether the perceived benefits of LARC can help alleviate the difficult problem of unintended pregnancy in the US. If so, the results will help stimulate progress toward that goal. PUBLIC HEALTH RELEVANCE: Unintended pregnancy continues to be a major public health problem in the US. A possible solution exists but remains underutilized: long-acting reversible contraception. New, high-quality research is needed to determine what role improved access to long-acting methods can have on reducing unintended pregnancy;the proposed study intends to find an answer that will have actionable impact.